.mainBox{
    padding:  0 10px;
    box-sizing: border-box;
    position: relative;
    height:-webkit-calc(100% - 70px); 
    height:-moz-calc(100% - 70px); 
    height:calc(100% - 70px); 
}
.ant-pagination-options-size-changer.ant-select{
    margin-right: 0;
}